If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

It's a test that will check your IQ.

Suppose you have one 11 minute hourglass and one 13 minute hourglass.

Can you measure exactly fifteen minutes using them ?

Before Mount Everest was discovered, what was the highest mountain in the world?

By including only four matchsticks in below picture, you have to make "Four Triangles And Two Squares"

You are presented with three boxes. One of them has a red ball inside and the other two have a black ball inside each of them. You are asked to pick up the one with red ball and you pick one. Now, one of the other boxes is opened and it is found to have a black ball.

You are presented with a chance to change your box with the one that is left closed. Will you change your box? Why or why not?

What does this rebus riddle mean?

Doctor Alex and a bus driver John are both in love with the same woman named Olivia. The bus driver need to go for a long trip of 10 days, Before he left he gave Olivia 10 apples.

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

A woman named Maria was at the funeral of her mother. She met a nice young man that she had never seen before and after the service, they spent a bit of time together. Then she got busy and didn’t get his name or phone number before he left. She tried to find him, but no one knew who he was or how to contact him. A few weeks later, Maria’s older sister dies and the police suspect murder. Who killed the sister?